new and rare Crustacea from Scotland. 58 
terer Maxillarfuss schmiichtig, mit einem Greifhaken versehen. 
Furcalanhinge beim ¢ und ? verschieden gestaltet. Zwei 
Eiersiicke.”’ 
Thalestris mysis, Claus. 
This very distinct species was during the last summer 
observed by us for the first time in the Firth of Forth. The 
large foliaceous fifth pair of swimming-feet are closely and 
obliquely striate, the stria being quite distinct. Thalestris 
mysis appears to be comparatively rare in Britain; there are 
few Scotch records for it, and its occurrence in the Forth is 
therefore of interest. 
EXPLANATION OF THE PLATES. 
PiatTeE V. 
Leptopsyllus intermedius, sp. n. 
Fig. 1. Female, seen from the side, x 80 (A, front view of ovisac). 
2. Anterior antenna, < 500. 3. Posterior antenna, x 500. 
4. Mandible and palp, x 500. 5. Foot of first pair of swim- 
ming-feet, x 5380. 6, Foot of second pair, x 380. 7. Foot of 
fourth pair, x 380. 8. Fifth pair, female, x 258. 9. Fifth 
pair, male, x 253. 10. Abdomen and caudal stylets, dorsal 
view, X 80. 11. Male spermatophore, x 380, 
Mesochra spinicauda, sp. n. 
Fig. 12. Female, seen from the side, X 80. 13. Anterior antenna, female, 
x 380. 14. Anterior antenna, male, x 3880. 15. Posterior 
antenna, X 380. 16, Mandible and palp, x 380. 17. Maxilia, 
x 380. 18. Anterior foot-jaw, x 3880, 19. Posterior foot-jaw, 
x 3880. 20. Foot of first pair of swimming-feet, x 3480. 
21. Foot of fourth pair, x 380. 22. Foot of fifth pair, female, 
x 880. 25. Foot of fifth pair, male (A, appendage to first 
abdominal appendage), x 380. 24. Abdomen and caudal 
stylets, dorsal view, X 80. 25. Male spermatophore, x 380. 
Mesochra MacIntoshi, sp. n. 
Fig. 26. Posterior foot-jaw, x 760. 27. Abdomen and caudal stylets, 
dorsal view, x 80. 
PuateE VI. 
Mesochra MacIntoshi, sp. n. 
Fig. 1. Female, seen from the side, X 80. 2. Anterior antenna, x 2533, 
3. Posterior antenna, X 253. 4. Mandible and palp, x 880. 
5. Foot of first pair of swimming-feet, x 383. 6. Foot of fourth 
pair, xX 253. 7. Foot of fifth pair, x 380, 
Pseudowestwoodia pygmea, sp. n. 
Fig. 8. Female, seen from the side, x 80. 9. Anterior antenna, x 380. 
